Lead alloy



Composition Grams oxide ,Reilned rt 1 0. am Refined Pb 0.03 Sb 4. 79 Refined Pb 0.08% sbigms 1.5 Refined Pb-H]. 3b .MP 1.

Patented June 20,1939

PATENT OFFICE LEAD ALLOY Jesse 0. Betterton and Yurii E. Lebedeif, Metuchen, N. J., assignors to American smelting and Refining Company, New York, N. Y., a corporation of New Jersey No Drawing. Original application March 24,

1936, Serial No. 70,607.

Divided and this application December 3, 1938, Serial No. 243,780

3 Claims. (Cl. -168) This invention relates to lead alloys and particularly concerns the improvement of certain lead alloys with respect to their oxidizing characteristics.

In the manufacture of cable sheathing, pipe, sheeting and the like, it has been proposed to utilize lead containing a small amount of another metal or other metals'which impart to the alloy certain desired characteristics, e. g. increased tensile strength, improved resistance to corrosion, greater hardness, etc. Among the elements proposed are antimony'and arsenic which occupy adjacent positions in the second family of elements in Group V of the Periodic Table.

While such lead alloys have proven themselves superior to lead with respect to the properties for which they have been employed, nevertheless an undesired characteristic accompanies the addition of these elements to lead, namely, the tendency of the alloy compositions toward excessive oxidation. That the susceptibility of such alloys to excessive oxidation is a serious disadvantage is very apparent in the extrusion of cable sheathing where the oxidation products become incorporated in the sheath causing weakness and areas favoring the inception of corrosion.

It has n w been found that by incorporating phosphorus in amounts not exceeding approximately 0.01% in a lead alloy containing not more than approximately 0.5% of antimony or arsenic, or both, the tendency of the alloy toward excessive oxidation is reduced to a very great extentand this highly desirable result is obtained without materially affecting the tensile strength of the composition.

In determining the oxidation of the various compositions investigated, the following procedure was followed in all cases: a 500-gram sample of the composition wasmelted in a casserole and the surface stirred for ten minutes at a temperature of 355 C. by means of a rotating paddle operated at R. P. M. The dross was then skimmed and weighed after which the oxide was dissolved It will readily be seen from the above examples that whereas the lead alloyed with antimony alone exhibited a decided tendency to oxidize as compared to refined lead, the addition of only a small amount of phosphorus very markedly diminishes that characteristic. Further, as hereinbefore stated, this beneficial eifect is accomplished without material adverse eifect upon the tensile v strength. .To illustrate:

Tensile Composition stren h- (Psi Refined Pb 1905 Refined Pb+0.207 As+0.007 P 2825 Refined Pb+0.05 O Bb+0.007 P 2920 and/or arsenic would adversely affect other desired properties of the particular alloy.

The present application is a division of Betterton and Lebedefl, Serial No. 70,607, filed March 24, 1936 for Lead alloys.

What is claimed is:

1. An oxidation resistant alloy consisting of 0.001% to 0.01% phosphorus, 0.05% to 0.5% of an alloying element selected from the group consisting 'of antimony and arsenic, and the balance lead.

2. An alloy consisting of antimony not exceeding 0.5%. Dhosphorusin an eifective amount but not exceeding 0.01% and the balance lead.

3. An alloy consisting of arsenic not exceeding 0.5%. phosphorus in an efiective amount but not exceeding 0.01% and the balance lead.

mesa o. nn'rrnn'ron. 

